Koi is a naturally friendly, amiable type of person. He is good at socializing, making him a person with lots of friends from either gender, and always encourages those who feel down. He is also described to be earnest, hard-working, straightforward, and quite well-informed. Because of this, he's made some startling connections. As a result of his naturally extroverted personally, Koi gets along very well with their staff members. Furthermore, he resembles the role of a big brother by looking out for everyone, despite being doted upon by those older than him. He's also quite the mood-maker, and plays the funny man role and can throw sharp retorts, making him a reliable member of his unit. According to his profile, while he may look like a player, he has a strong moral sense.